In Patent Document 1, a positive bus bar for connecting positive electrodes of a plurality of cylindrical batteries and a negative bus bar for connecting negative electrodes thereof are provided. The positive and negative electrodes of the cylindrical batteries are connected to respective bus bars via a fuse (a current limiter). A lead wire is used as the fuse, and when a current of a predetermined value or more such as an excess current flows, fusing is caused due to heat generation, so that electric connection between the bus bar and the positive electrode of the cylindrical battery and/or electric connection between the bus bar and the negative electrode of the cylindrical battery are/is cut off.